Monday, July 14, 2008

9.2 Mars

No one can forget the excitement upon seeing this image, taken in 1976 by the Viking spacecraft then orbiting Mars. Clearly it is a face complete with eyes (well, at least one), nose, and mouth. Some claimed that computer enhancement showed an eyeball with the pupil (the right eye) plus a tear drop below the eye. In 1998, the Mars Global Surveyor re-photographed the same region and the face now looked somewhat different, the "eye", sadly, either was never there or had disappeared:

So the Martians most likely did not construct the site, if there had been Martians in the first place.

Now the Phoenix Mars Lander tells us, there is ice on Mars and the Martian soil is similar to that found in our backyards. For those who grew up with Ray Bradbury's the Martian Chronicles (1950), the new info is simply a re-affirmation of what maybe, even though no Martians are found just yet. Of course, Marvin the Martian (and his eyes) has been around to entertain us for a long long time:Now, remember this 1990 movie, "Total Recall", starring ArnoldFast forward your DVD to the part when Douglas Quaid and Melina get blown out of the enclosures onto the surface of Mars and are now exposed to the Martian environment, i.e., the vacuum. Their bodies begin to bloat. The change of their eyes is especially alarming as they begin to bulge out of the eye sockets. However, as soon as the alien machine starts to alter the Mars atmosphere to that resembling the Earth, both Quaid and Melina recover nicely. Their eyes look entirely normal with no loss in function - as if nothing untoward has happened. Right there is your clue that something is amiss in this explosive decompression episode. If the eyeball can expand at all, it'll only be the conjunctiva. The retina does not have the elasticity to allow stretching and is certain to disrupt, just like wet tissue paper. So an episode such as that depicted in the movie can lead to blindness.

It is often assumed that a person explodes when exposed to the non-pressure of the outer space. In reality, for a human being to decompress from 1 atm to zero, nothing much happens, because the skin is tough enough to withstand such a small change. The sclera of the eyeglobe is especially strong because it is constituted of overlaying collagen fibers. A slight inflation, yes. Explosion, no. Oh, the death is from asphyxiation, naturally.

There has been only one catastrophic explosive decompression of unimaginable force. That is the Byford Dolphin diving bell accident of 1983. In which, 4 divers inside the bell died from a sudden pressure drop from 8 to 1 atm owing to the sudden opening of a hatch (the diver who opened the hatch also died). The Byford Dolphin is a Norwegian oil exploration rig then operating in the North Sea. The divers were undergoing gradual decompression when the accident occurred. One of them closest to the hatch literally did explode. The others showed blood lipoprotein denaturation, organ hemorrhages, and large amount of gas in blood vessels. One diver had a large sub-conjunctival blister suggesting a separation of the conjunctiva from the sclera.

It is possible that the script writers of "Total Recall" had perused the Byford Dolphin forensic reports, hence the eye scene.

Unfortunately, in a world now starving for oil, we foresee a rush to off-shore oil exploration and deep-sea drilling. We must all remember that safety for the workers/divers is a first priority and deservedly so.

Very good point, Cube. Wonder how soon that'll become. Of course there are technical issues involved. Plus other minor albeit important issues, e.g., what happens if you become bored on the way over. Read?